According to witnesses, the BBC reports, on September 4, 2005, seven New Orleans policemen shot at a group of unarmed* civilians trying to cross the Danziger Bridge in an attempt to get food from a grocery store. Two of the civilians, including "Ronald Madison, a 40-year-old mentally disabled man, and James Brissette, 19, were shot and killed, and four other people were wounded." The police officers were facing charges ranging from attempted second-degree murder to first-degree murder until the other day when District Judge Raymond Bigelow threw out the charges because "prosecutors had violated state law by divulging secret grand jury testimony to a witness" and that "prosecutors had wrongly instructed the grand jury, and that grand jury testimony by three of the officers was used against them improperly."
Though it seems like The New York Times should have mentioned something about this, searches for "katrina shooting," "katrina police" and other possible terms turn up no relevant results. The misapplication of police violence during a catastrophic natural disaster is no small thing. In his excellent essay "Critique of Violence," Walter Benjamin argues that it is exactly this kind of use of police power that threatens democracy and the rule of law. Yet: nothing.
*Though the officers claimed that they opened fire only after being shot at, "Investigators later revealed that at least some of the shooting was by residents trapped by floodwater trying to attract the attention of rescue parties."